State's coast gets weather radar system

By:  Les Blumenthal
Source: The Tri-City Herald

WASHINGTON -- A new state-of-the-art radar system on the Washington coast will make it easier for meteorologists to track heavy weather coming off the Pacific Ocean even as some scientists say the intensity of winter storms and waves pounding the Northwest shore is increasing.

Until now, the Washington coastline has been the only coastal area in the continental U.S. without weather radar coverage.

The region's storms more than rival the hurricanes and Nor'easters elsewhere in the nation. A storm on Columbus Day in 1962, considered the most intense nontropical storm to hit the U.S. in a century, had sustained winds along the coast of 150 miles per hour with gusts to 180.

"If it hit today, it would cause Katrina-like damage," said Cliff Mass, a professor of atmospheric sciences at the University of Washington. "We get some of the most intense storms in the world. We have no radar."

The National Weather Service is expected to announce the site for the new radar installation in the coming months, likely in Grays Harbor County. It should be operational by 2012, said Brad Colman, meteorologist in charge of the Weather Service's Seattle office. "We are moving as quickly as we can," he said.

As the National Weather Service moves forward with design and construction of the new radar, scientists at Oregon State University's department of geosciences, using data from buoys far offshore, have concluded that wave heights and the power of winter storms have been on the upswing over the past nearly 30 years.

Studies using data from a lightship stationed off the southwest coast of Britain and buoys off the U.S. Atlantic Coast have reached similar conclusions.

"While these increases are most likely due to Earth's changing climate, uncertainty remains as to whether they are the product of human-induced greenhouse warming or represent variations to natural multi-decadal climate cycles," says a report scheduled for publication in the journal Coastal Engineering.

The study found that median waves off the Northwest coast are more than a foot higher than 30 years ago. The very largest waves are between 8 and 10 feet higher. During the largest storm, offshore waves can be more than 45 feet tall.

"It's pretty wild out there," said Peter Ruggiero, an assistant professor at Oregon State University and one of the authors of the study.

The size of the larger waves is increasing faster than the size of smaller waves, Ruggiero said, and the size of the waves off Washington is growing faster than those off Oregon. He also said the increased size of waves is more of a threat to coastal areas than the increase in ocean levels.

Ruggiero said he and other researchers who worked on the study are sensitive to criticism that the findings were based on only 30 years of data.

"We would like longer records," he said. "But without a doubt we see a trend in the data."

Damage from the violent, dangerous storms blowing in from the North Pacific is not limited to the Northwest coastline.

In December 2007, a storm with winds that gusted on the coast to nearly 140 mph brought torrential rains to parts of Western Washington.

Bremerton received a record 10 inches of rain in 24 hours, and extensive flooding in Lewis County closed Interstate 5, the major north-south highway on the West Coast, for three days. Fourteen people were killed and property damage was estimated at more than $1 billion.

Since 1953, there have been 41 presidential disaster declarations involving Washington, most of them for flooding and high winds. The state was tied for 15th among 59 states and territories in the number of disaster declarations between 1953 and 2008.

The University of Washington's Mass and others said better radar coverage on the coast could have helped forecasters issue warnings, especially flood warnings for inland areas like those during the 2007 storm.

A congressionally requested report released last spring said the precise track and intensity of storms coming off the Pacific is often "difficult to analyze and predict" with existing radar.

There are currently two major weather radar stations in the Northwest -- on Camano Island in Puget Sound north of Seattle and in Portland. Those radars are 20 to 25 years old.

But the Olympic Mountains block the Camano Island radar's view of the Washington Coast. The Coast Range interferes with Portland radar's view of the northern Oregon and southern Washington coasts.

"Virtually no radar coverage is available over the ocean where the majority of Western Washington's weather originates," last year's report found.

Forecasters now use satellite and buoy data along with numerical models to track storms. But satellites don't provide the same detail as the Doppler radar planned for the Washington Coast.

Mass said satellite data is like just examining a sick person, while the Doppler radar is like a CAT scan that can look inside.

The new coastal radar has a maximum range of about 250 miles and will provide fine detail of storms 150 miles out in the Pacific.

"This radar will improve forecasting not only for the coast, but for Puget Sound and even Central and Eastern Washington," Mass said.

The National Weather Service's Colman said the new radar won't solve all forecasting problems in the region.

"Some of the expectations are a little unrealistic," he said. "But it will certainly help."

More than $9 million in funding for the new radar station has been provided, using economic recovery funding and a congressional appropriation secured by Sen. Maria Cantwell, D-Wash.

Cantwell said the radar should help the region avoid the "nasty surprises" that can come from the major Pacific storms.

"We usually know from space imagery when big storms are coming, but it's the coastal radar that will finally give coastal communities and residents in the Puget Sound area the detailed forecasting information they need to cope with these often-catastrophic and sometime life-threatening weather events," Cantwell said.